Longstreet Farm was among the largest and most prosperous farms in Holmdel. The original 495 acres were assembled in 1806 by Hendrick Longstreet from several farms. During the 1890s, it was owned by his daughter Mary Ann Longstreet, who was in her seventies. The farm was managed at that time by Hendrick's great-grandson Jonathan I.Holmes, who was in his twenties.
During the 1890s, Longstreet was a general farm on which tenant farmers raised cereal grains, livestock, and potatoes as a cash crop.
Farm practices in Monmouth County were changing in response to competition from midwestern farmers and to mechanization sparked by the Industrial Revolution. General farms that primarily used horse power, such as Longstreet Farm, were slowly being replaced by farms which relied on market gardens and used steam and gasoline power. In the 1890s, Longstreet Farm was considered an old-style farm.
Jonathan I. Holmes inherited the farm in 1911 from his aunt, Mary Ann Longstreet. The farm remained in the family until it was purchased by the Monmouth County Park System in 1967 from Jonathan's daughter and heir, Mary Longstreet Holmes Duncan. Since then, the farm has been preserved as a slice of the county's rural past. The farm opened to public in 1972.
The Longstreet Farmhouse was built in three sections between 1775 and 1840. Structural changes made in the 20th century were eliminated when restoring the farmhouse in the 1890s period. The farmhouse contains 14 rooms and the house is open to the public on weekends and holidays from March through December, noon to 3:30 pm or by reservation. The grounds are open everyday from 10am - 4pm; 9am - 5pm Memorial Day to Labor Day.